Spatial Distribution of Soil Moisture in Vineyard in Arid Region of Northwest China

The arid region of Northwest China has become a major wine grape cultivation base,and the soil moisture is important for grape growth and quality.So we need to obtain accurate soil moisture condition for fine irrigation management.The research was carried out at a vineyard in Wuwei City which located at an arid region in Northwest China,and sixty sampling points collected on a 30 m grid.Soil moisture was measured at three depths in soil profile: 10~20 cm for the soil surface,20~80 cm in grape root zone,80~100 cm in deep layer.The data was analyzed with a combination of classical statistics and geological statistic.The research results showed that all layers of soil moisture were normal distribution,and all the layers of soil moisture exhibited moderate spatial variability,in the tendency of increasing first and then decreasing with depth increases;and all soil water was correlated in spatial range,the range of theoretical variation functions of soil moisture correlation distance was 117.04 m,167.92 m and 174.81 m;The soil moisture distribution map which was charted by Kriging interpolating can provide reference for formulating irrigation system;The rational sampling number for soil moisture was given under different believable level and exactitude through the classic statistics analysis.